1. Field of the Invention
The present invention generally relates to a tool for applying films having an adhesive backing to articles and, more particularly to a hand held, fluid driven film applique tool useful in applying such film to surfaces having raised protrusion, such as fastener heads or the like.
2. Background Discussion
A team composed of Lockheed Martin and 3M are investigating the potential benefits of using "paintless" film appliques instead of paint on commercial and military aircraft. These aircraft appliques consist of adhesive films designed to offer potential savings over conventional paint in production costs, support requirements and aircraft weight. They also offer significant environmental advantages, since commercial and military painting are a major source of volatile organic compounds (VOC's).
Paintless aircraft coatings, when properly applied, can withstand forces of up to 5 g's and speeds up to Mach 1.4. While the average paint coating lasts approximately 3 years, these paintless coatings last up to 5 years and involve no use of solvents in its application or removal.
Most aircraft are painted frequently. Military aircraft have camouflage repainted every time they move to a different theatre of war and airlines have a different livery painted on them every time they are leased to a new operator. Every time this is done, the aircraft must be isolated in a paint shop to protect employees and the environment from a range of toxic solvents and additives present in every paint as well as other VOC compounds which are heavily used in the application and removal of paint coatings.
The self-adhesive plastic films used by paintless technology are quite similar to Teflon and can be printed with the desired livery, camoflague pattern or miliary markings and cut out to the right shape by a computer for application to the complex contours of a particular aircraft type. These sheet are applied under pressure and have no effect on the flying ability of the aircraft.
The paintless film is peeled off using hot, high-pressure water and disposed of as non-hazardous waste. New film is applied by hand in a manner similar to wallpaper. For application to the aircraft, the film is cut into individual pieces (for example 400 or more) using gore cuts to follow the aircraft's curved surfaces. Butt and lap joints are used and edge sealer applied to prevent peeling. Applique shapes can be stored in computer and cut form flat film on demand, using a plotter/cutter when recoating an aircraft. In addition, the paintless film can be applied during routine maintenance, while other work continues on the aircraft.
Proper application of the paintless film requires uniform adhesion of the film to the surface without wrinkles, tears, tenting or creases. This is particular difficult for aircraft, since aircraft surfaces are studded with fasteners, such as, for example, rivets, screws and the like, which have heads the protrude above the surface of the aircraft. These protrusions tend to create tenting of the paintless film which is unacceptable according to the specification requirements of the film. Moreover, the protrusions make it difficult to apply the proper amount of uniform pressure to the film to assure correct bonding of the film's adhesive backing to the aircraft surface.
Heretofore, application of the paintless films at and around the fastener heads on aircraft surfaces has been achieved by applying pressure to the film with the finger tips of the human hand or using a felt squeegee. This is a very time consuming and labor intensive process which creates non-conforming inconsistences which vary from fastener to fastener.